TW201724676A - Surge protection element - Google Patents

Abstract

To provide a surge protection element such that sublimation disappearance of a discharge assisting portion can be suppressed, and durability can be improved. The invention comprises: an insulating tube 2; a pair of sealing electrodes obstructing the openings at both extremities of the insulating tube to seal therein a discharge control gas; and a discharge assisting portion 4 formed on the inner peripheral surface of the insulating tube. The pair of sealing electrodes has a pair of protruding electrode portions protruding in the inner direction and facing one another. The discharge assist portion constitutes : a layer stack comprising an insulating layer 8 formed from an insulating material; and ion source layers 9 respectively above and below the insulating layer, and formed from an ion source material.

Description

Surge protection element

The present invention relates to a surge protection member that is used to protect various machines from the influence of a surge caused by a lightning strike or the like, and to prevent an accident in advance.

In the telephone, fax machine, data machine and other communication equipment, the connection between the electronic equipment and the communication line, the power line, the antenna, or the CRT, LCD TV, and plasma TV display drive circuit, etc. are susceptible to lightning surge or static electricity. The portion of the electric shock caused by the abnormal voltage (surge voltage) is connected to the surge protection element in order to prevent the electronic device or the printed circuit board on which the device is mounted from being damaged by thermal damage or ignition due to abnormal voltage.

In the related art, for example, an arrester type in which a pair of protruding electrode portions projecting in a facing state by a pair of sealing electrodes and a discharge assisting portion are formed on the inner surface of the insulating tube is described. Surge protection element. Generally, in the surge protection element as described above, the discharge assisting portion formed of the carbon material is formed on the inner surface of the insulating tube that faces the intermediate portion between the pair of protruding electrode portions. The discharge auxiliary portion shown above is generally a conductive ion source such as graphite. The material is formed to form an ion source to promote initial discharge.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese New Registration No. 3151069

The following problems remain in the above-mentioned prior art.

In the conventional structure, a part of the discharge assisting portion disappears due to heat and expansion energy during arc discharge generated between the pair of protruding electrode portions, and the discharge voltage at the time of reverse discharge becomes unstable (discharge voltage rises) )The problem.

In particular, in the discharge of a large current, the sublimation of the discharge assisting portion tends to be remarkable. Further, if the discharge current greatly exceeds the guaranteed range, it is required to change the electrode design, and it is necessary to increase the size of the electrode or the parallel connection in order to stabilize the operation.

In addition, it is considered that the discharge assisting portion is only thickened, and the sublimation of the discharge assisting portion is suppressed. However, during the discharge, the discharge assisting portion disappears from the insulating surface of the insulating tube, and thus a sufficient suppressing effect cannot be obtained.

The present invention has been made in view of the above problems, and it is an object of the invention to provide a surge protection element capable of suppressing an unstable operation due to the disappearance of sublimation of a discharge assisting portion.

The present invention has the following configuration in order to solve the above problems. In other words, the surge protection device according to the first aspect of the invention includes: an insulating tube; a pair of sealing electrodes that close the opening of both ends of the insulating tube and seal the discharge control gas therein; and a discharge assisting portion on an inner circumferential surface of the insulating tube, wherein the pair of sealing electrodes have a pair of protruding electrode portions that protrude inward and face each other, and the discharge assisting portion is made of an insulating layer made of an insulating material. And a layer of an ion source layer formed of an ion source material on the upper and lower sides of the insulating layer.

In the surge protection device of the present invention, the discharge assisting portion is composed of an insulating layer formed of an insulating material and a layer of an ion source layer formed of an ion source material on the upper and lower sides of the insulating layer. Even if the ion source layer exposed on the surface disappears due to discharge, together with the ion source layer on the surface, the underlying insulating layer also sublimates and disappears to expose the next ion source layer, thereby maintaining the discharge assisting function.

In the first aspect of the invention, the discharge assisting unit is characterized in that the ion source layer and the insulating layer are alternately laminated, and at least two or more layers of the insulating layer and three or more layers of the ion source are provided. Floor.

In other words, in the surge protection element, the discharge assisting portion is formed by alternately stacking the ion source layer and the insulating layer and having at least two or more insulating layers and three or more ion source layers, so that the ion source layer disappears with sublimation. Further, at least three times or more are repeatedly exposed, whereby a stable operation can be obtained even when the discharge is repeated.

The surge protection element of the third invention is in the first or second In the above, the insulating layer is formed of ruthenium oxide.

That is, in the surge protection element, since the insulating layer is formed of yttrium oxide, it is easy to sublimate and disappear by the thermal energy at the time of arc discharge, and the next ion source layer can be exposed.

In any one of the first to third aspects of the present invention, the plurality of discharge assisting portions are formed in a circumferential direction of an inner circumferential surface of the insulating tube, and at least one of the plurality of discharge auxiliary portions One of the aforementioned insulating layers having a thickness set to be different from the others.

In other words, in the surge protection element, at least one of the plurality of discharge auxiliary portions having the thickness of the inner circumferential surface of the insulating tube has an insulating layer different in thickness from the other. In the discharge arc energy, even if the discharge assisting portion of the insulating layer having a specific thickness disappears, the discharge assisting portion having the insulating layer having another thickness remains, whereby the discharge assisting function can be maintained.

According to the present invention, the following effects are achieved.

That is, according to the surge protection device of the present invention, the discharge assisting portion is composed of an insulating layer formed of an insulating material and a layer of an ion source layer formed of an ion source material on the upper and lower sides of the insulating layer. Therefore, even if the ion source layer exposed on the surface disappears due to discharge, together with the ion source layer on the surface, the underlying insulating layer also sublimates and disappears to expose the next ion source layer, thereby maintaining discharge assistance. Features.

Therefore, even if the surge current or the number of discharges increases, it can be well maintained. With the performance of surge protection components. In particular, the surge protection element of the present invention is suitable for power supply and communication equipment for infrastructure construction (railway connection, regenerative energy related (solar battery, wind power generation, etc.)) requiring high current surge resistance.

1‧‧‧ surge protection components

2‧‧‧Insulated tube

3‧‧‧Seal electrode

4, 24A, 24B, 24C‧‧‧ discharge auxiliary department

5‧‧‧ protruding electrode

7‧‧‧Flange

8, 8a, 8b, 8c‧‧‧ insulating layer

9‧‧‧Ion source layer

C‧‧‧Axis of insulating tube

Fig. 1 is an enlarged cross-sectional view showing the essential part of a first embodiment of the surge protection element of the present invention.

Fig. 2 is a cross-sectional view showing the axial direction of the surge protection element in the first embodiment.

Fig. 3 is a perspective view showing a principal part of the insulating tube in a second embodiment of the surge protection element according to the present invention.

Fig. 4 is an enlarged cross-sectional view showing a main part of each discharge assisting portion in the second embodiment.

Hereinafter, a first embodiment of the surge protection element of the present invention will be described with reference to Figs. 1 and 2 . In each of the drawings used in the following description, the scale is appropriately changed in order to form each member into a size that can be recognized or easily recognized.

As shown in FIGS. 1 and 2, the surge protection element 1 of the present embodiment includes an insulating tube 2, and a pair of sealing electrodes that seal the discharge control gas inside by closing the opening portions of the insulating tube 2 at both ends. 3; and shape The discharge assisting portion 4 is formed on the inner circumferential surface of the insulating tube 2.

The pair of sealing electrodes 3 have a pair of protruding electrode portions 5 that protrude inward and face each other.

Further, the discharge assisting portion 4 is composed of an insulating layer 8 made of an insulating material and a layer of an ion source layer 9 formed of an ion source material on the upper and lower sides of the insulating layer 8.

Further, the discharge assisting portion 4 is formed by alternately stacking the ion source layer 9 and the insulating layer 8 and having at least two or more insulating layers 8 and three or more ion source layers 9. In other words, the discharge assisting portion 4 has a structure in which the ion source layer 9 / the insulating layer 8 / the ion source layer 9 are laminated on the inner peripheral surface of the insulating tube 2, and the lowermost layer on the side of the insulating tube 2 The uppermost layer as the outermost surface is formed as the ion source layer 9. In the present embodiment, the discharge assisting portion 4 composed of a laminate of four ion source layers 9 and three insulating layers 8 is formed.

The discharge assisting portion 4 is formed linearly on the inner circumferential surface of the insulating tube 2 along the axis C of the protruding electrode portion 5.

The ion source layer 9 is a discharge auxiliary portion formed of a conductive material such as a carbon material.

The insulating layer 8 is formed of the same material as the insulating tube 2 or a material contained in the insulating tube 2. For example, when the insulating tube 2 is formed of a crystalline ceramic material such as alumina containing cerium oxide such as SiO ₂ , the insulating layer 8 is formed of a ceramic material containing cerium oxide ( vermiculite) such as SiO ₂ .

Wherein, in the case of the insulating layer 8, oxidation may be additionally used. Insulating materials such as ceramic materials such as magnesium and zirconia. Further, the insulating layer 8 is formed to cover the ion source layer 9, but may be formed in a larger area than the ion source layer 9, and a part thereof may be formed directly on the inner peripheral surface of the insulating tube 2.

In the method of laminating the ion source layer 9 and the insulating layer 8, for example, the raw material powder and the organic binder which are the insulating layer 8 are mixed and formed into a slurry shape. Next, a green sheet was produced using a roll coater, and the slurry was used to form a thin sheet. Further, the green sheet was cut and coated with graphite as an ion source. Next, a green sheet was laminated so as to sandwich the graphite, thereby producing a laminate. Next, when the insulating tube 2 is fired, the layered body is adhered to the inside of the insulating tube 2, and fired together with the insulating tube 2, whereby the layer of the ion source layer 9 and the insulating layer 8 can be laminated.

For example, the thickness of the single layer of the ion source layer 9 is set to 10 μm, and the thickness of the single layer of the insulating layer 8 is set to 100 μm.

The sealing electrode 3 is made of, for example, a 42 alloy (Fe: 58 wt%, Ni: 42 wt%) or Cu or the like.

The sealing electrode 3 has a disk-shaped flange portion 7 that is fixed to an intimate state by heat treatment by a conductive fusible material (not shown) in the opening portions at both ends of the insulating tube 2. A cylindrical protruding electrode portion 5 that protrudes inward and has an outer diameter smaller than the inner diameter of the insulating tube 2 is integrally provided inside the flange portion 7.

The insulating tube 2 is a crystalline ceramic material such as alumina. Among them, the insulating tube 2 may be formed of a glass tube such as lead glass.

The conductive fusible material is formed of an Ag-Cu brazing material, and is, for example, a hard-weld material containing Ag.

The discharge control gas sealed in the insulating tube 2 is an inert gas or the like, and for example, He, Ar, Ne, Xe, Kr, SF ₆ , CO ₂ , C ₃ F ₈ , C ₂ F ₆ , CF ₄ , H are used. ₂ , the atmosphere, etc. and these mixed gases.

In the surge protection element 1, when an overvoltage or an overcurrent enters, first, an initial discharge is performed between the discharge assisting portion 4 and the protruding electrode portion 5, and the initial discharge is used as a timing, and the discharge further progresses to a pair of flanges. The seventh portion or the protruding electrode portion 5 is discharged.

As described above, in the surge protection element 1 of the present embodiment, the discharge assisting portion 4 is formed of an insulating layer 8 made of an insulating material and an ion source material formed on the upper and lower sides of the insulating layer 8 respectively. Since the ion source layer 9 is formed by lamination, even if the ion source layer 9 exposed on the surface is sublimated by discharge, together with the ion source layer 9 on the surface, the underlying insulating layer 8 is simultaneously sublimated and disappeared, and the next step is revealed. The ion source layer 9 can thereby maintain the discharge assisting function.

Further, the discharge assisting portion 4 is formed by alternately stacking the ion source layer 9 and the insulating layer 8 and having at least two or more insulating layers 8 and three or more ion source layers 9. Therefore, the ion source layer 9 is repeatedly exposed with sublimation disappearance. At least three times or more, a stable operation can be obtained even when the discharge is repeated.

Further, since the insulating layer 8 is formed of ruthenium oxide, it is easy to sublimate and disappear due to thermal energy at the time of arc discharge, and the subsequent ion source layer 9 can be easily exposed.

Next, a second embodiment of the surge protection element of the present invention will be described below with reference to Figs. 3 and 4 . In the following description of the embodiments, the same components as those described in the above embodiments are denoted by the same reference numerals, and their description is omitted.

The second embodiment is different from the first embodiment in that one discharge assisting portion 4 is formed on the inner circumferential surface of the insulating tube 2, and the second embodiment is the second embodiment. In the surge protection element, as shown in FIGS. 3 and 4, a plurality of discharge assisting portions 24A, 24B, and 24C are formed on the inner circumferential surface of the insulating tube 2 at intervals in the circumferential direction.

Further, in the second embodiment, at least one of the plurality of discharge auxiliary portions 24A, 24B, and 24C has an insulating layer set to have a different thickness from the other.

In the second embodiment, the insulating layer 8b of the discharge assisting portion 24B is formed thicker than the insulating layer 8a of the discharge assisting portion 24A, and is smaller than the insulating layer 8b of the discharge assisting portion 24B. The insulating layer 8c of the discharge assisting portion 24C is formed to be thick.

For example, the thickness of the insulating layer 8a of the discharge assisting portion 24A is set to 100 μm, the thickness of the insulating layer 8b of the discharge assisting portion 24B is set to 150 μm, and the thickness of the insulating layer 8c of the discharge assisting portion 24C is set to 200 μm.

As described above, in the surge protection device of the second embodiment, at least one of the plurality of discharge assisting portions 24A, 24B, and 24C formed in the circumferential direction of the inner circumferential surface of the insulating tube 2 is set to be different from the other. In the same thickness of the insulating layer, even if the discharge assisting portion (for example, the discharge assisting portion 24A) having the insulating layer having a specific thickness disappears by the discharge arc energy, the discharge assisting of the insulating layer having another thickness remains. The portions (for example, the discharge assisting portions 24B and 24C) can thereby maintain the discharge assisting function.

However, the technical scope of the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the invention.

For example, in each of the above-described embodiments, the discharge assisting portion 4 is formed in a linear shape, but may be formed in other shapes such as a dotted line shape or a plurality of dot shapes, and these may be combined to form a complex number.

2‧‧‧Insulated tube

4‧‧‧Discharge Assistant

8‧‧‧Insulating layer

9‧‧‧Ion source layer

Claims (4)

A surge protection device comprising: an insulating tube; a pair of sealing electrodes that seal a discharge control gas inside by sealing the both end openings of the insulating tube; and forming the insulating tube inside the insulating tube In the discharge auxiliary portion on the circumferential surface, the pair of sealing electrodes have a pair of protruding electrode portions that protrude inward and face each other, and the discharge assisting portion is made of an insulating layer formed of an insulating material and the insulating property The upper and lower layers of the layer are each formed by a laminate of ion source layers formed of an ion source material. The surge protection device according to the first aspect of the invention, wherein the discharge assisting portion is characterized in that the ion source layer and the insulating layer are alternately laminated, and at least two or more layers of the insulating layer and three or more layers of the ion source are provided. Floor. The surge protection element of claim 1, wherein the insulating layer is formed of ruthenium oxide. The surge protection element according to the first aspect of the invention, wherein the plurality of discharge auxiliary units are formed in a circumferential direction of an inner circumferential surface of the insulating tube, and at least one of the plurality of discharge auxiliary units is set to be different from the other The aforementioned insulating layer of different thickness.